Why Google recommendations for multilingual urls don't correspond to what they use (hl=xx)?

Question

Google's recommendations for multilingual sites say that:

URL parameters site.com?loc=de Not recommended

But they use them for all their services like: google.com, play.google.com, support.google.com... Just try to add hl=xx to the URL and the language will be changed. They don't use subdomains or subdirectories. Sometimes they use top level domains like google.com.ua (for Ukraine), google.ru (for Russia). But they use them only for search and maps and it doesn't actually change the language, it's something like country targeting, not language one. You still need to add hl=xx in order to change the language.

Why they do this? They are contrary to their own recommendations.

Answer 1

The key issue is that Google isn't a big fan of query strings when it comes to indexing, and I know of some instances in my own experience where sites I have managed which have used query strings have only had content indexed where the query strings didn't have to be used and yet couldn't get verification from anywhere 100% stating that query strings where or where not supported.

Google does not use the URL or lang meta tags to decide the language of the page, the language is detected automatically based on the visible content of the page. The only reason to divide it by directory or DNS is to provide a clearer demarcation of languages for the end user.

Answer 2

Google does support URL parameters for language selection now. If you use a URL parameter, you will need to use rel alternate hreflang meta tags on every page (or in your sitemap) to point to the page in the other languages.

Using a country TLD, subdomain, or subdirectory is a bit easier. In those cases you can add each language to Google Search Console. Then hreflang tagging is optional.